title: Plasma levels of interleukin-6 and selective serotonin reuptake inhibitor response in patients with major depressive disorder.
abstract: OBJECTIVE
  We investigated the plasma levels of interleukin (IL)-6 and 5-HTT polymorphisms in patients with major depressive disorder (MDD). This is the first report, to our knowledge, of an investigation into the association between 5-HTT gene polymorphism, plasma IL-6 levels, and responses to selective serotonin reuptake inhibitors (SSRIs) in Japanese patients with MDD.
  
  
  METHODS
  One-hundred and eighteen patients (51 male, 67 female) who met the DSM-IV criteria for MDD were enrolled. Their ages ranged from 24 to 78 (mean ± SD = 44 ± 12) years. The patients were treated with SSRIs (paroxetine in 66 cases, sertraline in 42 cases) for 8 weeks.
  
  
  RESULTS
  The plasma levels of IL-6 were significantly higher in the SSRI responders than in the nonresponders (p = 0.0328), and the changes in plasma IL-6 levels correlated significantly with the changes in severity of depressive state (p = .0.007). No difference was found in baseline and the changes in plasma IL-6 levels between the patients with a 5-HTT gene (5-HTTLPR) L-carrier and those with S/S.
  
  
  CONCLUSIONS
  These results suggest that the plasma levels of IL-6 reflect the severity of MDD and that plasma IL-6 levels might be another biological-state marker for the depressive state. In addition, the 5-HTTLPR polymorphism might be independent of plasma IL-6 levels.
authors.affiliation: Department of Psychiatry, University of Occupational and Environmental Health, Kitakyushu, Japan.
authors.forename: Reiji
authors.initials: R
authors.lastname: Yoshimura
authors.forename: Hikaru
authors.initials: H
authors.lastname: Hori
authors.forename: Atsuko
authors.initials: A
authors.lastname: Ikenouchi-Sugita
authors.forename: Wakako
authors.initials: W
authors.lastname: Umene-Nakano
authors.forename: Asuka
authors.initials: A
authors.lastname: Katsuki
authors.forename: Kiyokazu
authors.initials: K
authors.lastname: Atake
authors.forename: Jun
authors.initials: J
authors.lastname: Nakamura
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D003865:Major Depressive Disorder / Q000097:blood* / Q000188:drug therapy / Q000235:genetics*; D005260:Female; D006801:Humans; D015850:Interleukin-6 / Q000097:blood*; D008297:Male; D008875:Middle Aged; D011110:Polymorphism, Genetic / Q000235:genetics*; D050486:Serotonin Plasma Membrane Transport Proteins / Q000235:genetics*; D017367:Selective Serotonin Reuptake Inhibitors / Q000627:therapeutic use*; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D015415:Biomarkers; D015850:Interleukin-6; D050486:Serotonin Plasma Membrane Transport Proteins; D017367:Selective Serotonin Reuptake Inhibitors; C493230:SLC6A4 protein, human
keywords: Hamilton Rating Scale for Depression; interleukin-6; major depressive disorder; selective serotonin reuptake inhibitor; serotonin transporter